Voltammetric Investigation of Inclusion Complexes of the Selected Succinimides with beta-Cyclodextrin and (2-Hydroxypropyl)-beta-Cyclodextrin

Abstract

The inclusion complexes of the selected, potentially biologically active, succinimides with beta-cyclodextrin (beta CD) and (2-hydroxypropyl)-beta-cyclodextrin (HP beta CD) were prepared. The formation of the inclusion complexes of the investigated monophenyl and diphenyl succinimide derivatives was confirmed using attenuated total reflection (ATR) study. Their electrochemical behavior was examined by cyclic voltammetry (CV) and square wave voltammetry (SWV) in 0.05 M NaHCO3 on a gold electrode. The stability constants for compound 1 were determined by cyclic voltammetry and calculated as K-beta CD = 350.87 M-1 and K-HP(beta CD) = 250.67 M-1. The SWV measurements reveal well defined peak at potential E-p = similar to 60 mV and the higher currents at E-p for both inclusion complex of the succinimides compared to the free compounds. The impact of chlorine atom in the phenyl moiety of succinimide derivatives on the activity in electro oxidation reaction is presented. Among the studied succinimides, according to SWV measurements, the most active is the monophenyl succinimide derivative (compound 1) in complex with beta CD. The difference of peak current of compound 1 + beta CD compared to compound 1 + HP beta CD and free compound is 6.3 and 35.2 mu A cm(-2), respectively.